1. Field of the Invention
The present invention relates to a coordinate inputting/detecting apparatus, and more particularly relates to an optical touch panel type coordinate inputting/detecting apparatus, that is integrated and used with an electronic white board or a large display apparatus, or used in conjunction with a personal computer, and that optically detects a coordinate position designated by a designating member, such as a pen, or a finger, for inputting or selecting information represented by the coordinate position designated by the designating member.
2. Discussion of the Background
A coordinate inputting/detecting apparatus is known in which, when a coordinate inputting surface of the coordinate inputting/detecting apparatus is pressed by a pen or when the pen approaches the coordinate inputting surface, an electrical change is caused by an electrostatic charge or an electromagnetic induction, and thereby the coordinate position of a point pressed or approached by the pen is detected.
Also, a touch panel type coordinate inputting/detecting apparatus using an ultrasonic wave is known in which, when a panel is touched, a surface elastic wave emitted across and over the panel is attenuated and thereby a touched position on the panel is detected, as described, for example, in Japanese Patent Laid-open Publication No. 61-239322.
However, in such a coordinate inputting/detecting apparatus that detects a coordinate position using an electrostatic force or an electromagnetic induction, an electrical switching function must be provided at a coordinate inputting surface of the coordinate inputting/detecting apparatus, thus increasing the manufacturing cost of the apparatus. Further, the pen must be connected to a main body of the apparatus, for example by a cable, which makes the operation relatively difficult.
Further, a coordinate inputting/detecting apparatus using an ultrasonic wave is generally configured assuming that a finger is used for a designating device. When a pen made of soft elastic material is used as the designating device, in writing a straight line with the pen on a panel, for example, although the attenuation of a surface elastic wave is reliably obtained when the pen is pressed against the panel, a sufficient contact of the pen with the panel is not obtained when the pen is moved, and thereby the line is broken. On the other hand, if the pen is pressed unnecessarily strongly while moving the pen for obtaining the sufficient contact with the panel, as the pen is moved, the panel receives a stress from the pen because of the elasticity of the pen. This causes a distortion in the panel, and a reverting force is exerted while the pen is moved. Therefore, in writing a curved line with the pen, the force of pressing the pen decreases such that the reverting force is greater than the pressing force. As a result, the attenuation of the surface elastic wave is not reliably obtained and thereby it is determined that the input is discontinued. Thus, the coordinate inputting/detecting apparatus using an ultrasonic wave has a problem in obtaining a high reliability of detecting an input when a pen is used as a designating device.
Further, various attempts have been made to solve the drawback of the above-described coordinate inputting/detecting apparatuses by providing optical type coordinate inputting/detecting apparatuses as described, for example, in Japanese Patent Laid-open publications No. 5-173699 and No. 9-319501. A touch panel type coordinate inputting/detecting apparatus having a relatively simple construction can be realized using such an optical type coordinate inputting/detecting apparatus.
Optical type coordinate inputting/detecting apparatus have recently become widely used in conjunction with a personal computer as an effective tool for inputting or selecting information in the personal computer. However, unlike a coordinate inputting/detecting apparatus using an ultrasonic wave, a coordinate inputting/detecting surface (i.e., a touch panel) of such optical type coordinate inputting apparatuses does not have a detecting function by itself, and an optical detecting area is provided at a position slightly apart from the coordinate inputting/detecting surface of the coordinate inputting/detecting apparatus. Therefore, a space deviation exists between the actual plane where, for example, an image (e.g., character) is drawn (written) with a finger, i.e., the coordinate inputting/detecting surface, and a plane where the coordinates of the drawn image (character) are detected, and contrary to the intention of a person drawing the image (character), a trail is caused on the drawn image (character), that is reproduced, for example, on a display. That is, in an optical type coordinate inputting/detecting apparatus, a point at which a finger separates from the touch panel is detected not in an instance when the finger actually separates from the touch panel, but when the finger separates from the touch panel by more than a certain distance. Therefore, before the finger reaches such a position separated from the touch panel by more than the certain distance and at which the finger is detected as separated from the touch panel, despite the finger having already separated from the touch panel surface and drawing of a desired character having been already completed, the finger is still detected as touching the touch panel (as being inserted in the coordinate inputting/detecting area). Thereby, an unintended line is drawn at a part of a reproduced image. Such a phenomenon of drawing an intended line is called a trailing phenomenon.
For example, as illustrated in FIG. 33, when a coordinate inputting/detecting area 200 is provided at a surface side of a touch panel 201, and if a finger 202 draws a line along the surface of the touch panel 201 and separates from the surface of the touch panel 201 upon ending the drawing at a point P, the finger 202 is continued to be detected by a detecting light, i.e. the finger 202 is detected as touching the touch panel 202, until reaching a point Pxe2x80x2 where the finger 202 leaves the coordinate inputting/detecting area 200, and at that point Pxe2x80x2 the finger 202 is first detected as separated from the touch panel 202. Accordingly, a drawing line 203 which is displayed at a surface of the touch panel 201 via a display device does not end at the point P but instead is shown as extending to the point Pxe2x80x2, and the part between the points P and Pxe2x80x2 is displayed as a trailing line 204. In practical drawing cases, for example, in drawing a Japanese Kanji character xe2x80x9cxe2x80x9d (xe2x80x9cnixe2x80x9d) as illustrated in FIG. 34A, a line is first drawn from a point {circle around (1)} to a point {circle around (2)}, and then the finger is separated from the touch panel 202 at the point {circle around (2)}. Thereafter, another line is drawn from a point {circle around (3)} to a point {circle around (4)}, and the finger is separated from the touch panel 201 at a point {circle around (4)}. In actual drawings, however, when the finger separates from the touch panel 201 at each ending portion 205 of the points {circle around (2)} and {circle around (4)}, the above-described trailing phenomenon occurs, such that a trailing line 204 of a whisker is generated at each ending portion 205 as illustrated in FIG. 34B, thereby deteriorating the visibility of the drawn characters. Therefore, after the drawing is completed, a troublesome operation, such as erasing the trailing 204 by manipulating an erasing tool, is necessary.
Further, some Japanese Kanji and Hiragana characters have a sweeping up portion, such as, for example, a sweeping up portion 206 of Japanese Kanji character xe2x80x9cxe2x80x9d (xe2x80x9csunxe2x80x9d) as illustrated in FIG. 34C, and a sweeping portion, such as, for example, a sweeping portion 207 of Japanese Hiragana character xe2x80x9cxe2x80x9d (xe2x80x9ctsuxe2x80x9d) as illustrated in FIG. 34E. Because these sweeping up and sweeping portions are requisite drawings in Japanese Kanji and Hiragana characters, it is necessary to distinguish these sweeping up and sweeping portions from a trailing line in the ending portion 205. FIGS. 34D and 34F illustrate examples of reproduced drawn Kanji character xe2x80x9cxe2x80x9d (xe2x80x9csunxe2x80x9d) and Hiragana character xe2x80x9cxe2x80x9d (xe2x80x9ctsuxe2x80x9d). As illustrated, a trailing line portion 204 is generated at each of the ending portions 205 and tip ends of the sweeping up portion 206 and the sweeping portion 207.
Thus, the above-described trailing problem in the optical type coordinate inputting/detecting apparatus is caused by a fact that a deviation exists between the actual designating condition of a designating member, such a finger, and the determination or the recognition of the designating device in the coordinate inputting area of the coordinate inputting/detecting apparatus. As a result, a determination as to whether the designating device is inserted in the coordinate inputting/detecting area or recognition of the designating member in the coordinate inputting/detecting area of the coordinate inputting/detecting apparatus is not reliably made.
The present invention has been made in view of the above-discussed and other problems and addresses the above-discussed and other problems.
Preferred embodiments of the present invention provide a novel coordinate inputting/detecting apparatus and method that precisely recognize a designating state of a designating device designating a drawing position in a coordinate inputting/detecting area, such that a relatively appropriate coordinate inputting/detecting processing is realized and a trailing phenomenon in a reproduced image is reduced.
Another preferred embodiment of the present invention provides a novel coordinate inputting/detecting apparatus and method that process a coordinate inputting/detecting process while taking into consideration characteristics of Japanese Kanji and Hiragana characters appearing at sweeping up and ending portions of the characters.
According to a preferred embodiment of the present invention, a novel coordinate inputting/detecting apparatus for optically detecting a position of a designating device inserted into a flat or substantially flat two-dimensional coordinate inputting/detecting area of the apparatus includes a coordinate determining device to determine two-dimensional coordinates of the designating device in the coordinate inputting/detecting area. A distance determining device determines a distance of the designating device from a surface of the coordinate inputting/detecting area when the designating device is located on or in vicinity to the coordinate inputting/detecting area. A storing device stores information of the two-dimensional coordinates determined by the coordinates determining device and information of the distance determined by the distance determining device so as to be associated with each other. A coordinates change detecting/storing device detects a change of the two-dimensional coordinates information stored in the storing device at a predetermined time interval and stores the detected change of the two-dimensional coordinates information. A distance change detecting/storing device detects a change of the distance information stored in the storing device at a predetermined time interval and stores the detected change of the distance information. A state allocating device allocates at least one designating state among designating states of the designating device stored in advance, based upon the coordinate change information detected and stored by the coordinate change detecting/storing device and the distance change information detected and stored by the distance change detecting/storing device.
According to another preferred embodiment of the present invention, a novel coordinate inputting/detecting apparatus for optically detecting a position of a designating device inserted into a flat or substantially flat two-dimensional coordinate inputting/detecting area of the apparatus includes a coordinate determining device to determine two-dimensional coordinates of the designating device in the coordinate inputting/detecting area. A distance determining device determines a distance of the designating device from a surface of the coordinate inputting/detecting area when the designating device is located on or in vicinity to the coordinate inputting/detecting area. A storing device stores information of the two-dimensional coordinates determined by the coordinates determining device and information of the distance determined by the distance determining device so as to be associated with each other. A coordinates change detecting/storing device detects a change of the two-dimensional coordinates information stored in the storing device at a predetermined time interval and stores the detected change of the two-dimensional coordinates information, and a distance change detecting/storing device detects a change of the distance information stored in the storing device at a predetermined time interval and stores the detected change of the distance information. Further, a ratio calculating device calculates a ratio between the coordinates change detected by the coordinates change detecting/storing device and the distance change detected by the distance change detecting/storing device, and a threshold value storing device stores at least one predetermined threshold value for the ratio. A comparing device compares the ratio calculated by the ratio calculating device and the threshold value stored by the threshold storing device, and a state allocating device allocates at least one designating state among designating states of the designating device stored in advance, based upon a result of the comparison by the comparing device.
According to still another preferred embodiment of the present invention, a novel coordinate inputting/detecting apparatus for optically detecting a position of a designating device inserted into a flat or substantially flat two-dimensional coordinate inputting/detecting area of the apparatus includes a coordinate determining device to determine two-dimensional coordinates of the designating device in the coordinate inputting/detecting area and a distance determining device to determine a distance of the designating device from a surface of the coordinate inputting/detecting area when the designating device is located on or in vicinity to the coordinate inputting/detecting area. A storing device stores information of the two-dimensional coordinates determined by the coordinates determining device and information of the distance determined by the distance determining device so as to be associated with each other. A coordinates change detecting/storing device detects a change of the two-dimensional coordinates information stored in the storing device at a predetermined time interval and stores the detected change of the two-dimensional coordinates information, and a distance change detecting/storing device detects a change of the distance information stored in the storing device at a predetermined time interval and stores the detected change of the distance information. Further, a gradient calculating device calculates a gradient of the distance change detected by the distance change detecting/storing device relative to the coordinates change detected by the coordinates change detecting/storing device, and a threshold value storing device stores at least one predetermined threshold value for the gradient. A comparing device compares the gradient calculated by the gradient calculating device and the threshold value stored by the threshold storing device, and a state allocating device allocates at least one designating state among designating states of the designating device stored in advance, based upon a result of the comparison by the comparing device.
According to the present invention, in the above coordinate inputting/detecting apparatuses, the state allocating device may include a determining device to determine, according to a result of the comparison by the comparing device, that the designating device has not been inserted into the coordinate inputting/detecting area when the ratio is greater than the threshold value, and that the designating device has been inserted into the coordinate inputting/detecting area when the ratio is equal to or smaller than the threshold value.
According to another preferred embodiment of the present invention, a novel coordinate inputting/detecting apparatus for optically detecting a position of a designating device inserted into a flat or substantially flat two-dimensional coordinate inputting/detecting area of the apparatus includes a coordinates determining device to determine two-dimensional coordinates of the designating device in the coordinate inputting/detecting area at a predetermined time interval, and an insertion/non-insertion state detecting device to detect an insertion/non-insertion state of the designating device relative to the coordinate inputting/detecting area. Further, a vetorization device converts information of a direction and a length of a change between two two-dimensional coordinates sequentially detected by the coordinates determining device at the predetermined time interval into a coordinates vector value. And, a sweeping up processing device processes, if a change of a first coordinates vector value, obtained by the vetorization device when the non-insertion state of the designating device is detected at a first two-dimensional coordinates by the insertion/non-insertion state detecting device, from a second coordinates vector value, obtained by the vetorization device at a second two-dimensional coordinates immediately before the first two-dimensional coordinates, is not greater than a predetermined value, a drawing line connecting between the second two-dimensional coordinates and a third two-dimensional coordinates immediately before the second two-dimensional coordinates so as to be reduced by a predetermined length.
According to still another preferred embodiment of the present invention, a novel coordinate inputting/detecting apparatus for optically detecting a position of a designating device inserted into a flat or substantially flat two-dimensional coordinate inputting/detecting area of the apparatus includes a coordinates determining device to determine two-dimensional coordinates of the designating device in the coordinate inputting/detecting area at a predetermined time interval, and an insertion/non-insertion state detecting device to detect an insertion/non-insertion state of the designating device relative to the coordinate inputting/detecting area. Further, a vetorization device converts information of a direction and a length of a change between two two-dimensional coordinates sequentially detected by the coordinates determining device at the predetermined time interval into a coordinates vector value. And, a trailing processing device processes, if a change of a first coordinates vector value, obtained by the vetorization device when the non-insertion state of the designating device is detected at a first two-dimensional coordinates by the insertion/non-insertion state detecting device, from a second coordinates vector value, obtained by the vetorization device immediately before the first two-dimensional coordinates, is greater than a predetermined value, a drawing line connecting between the first and second coordinates so as to be made null.
According to still another preferred embodiment of the present invention, a novel coordinate inputting/detecting apparatus for optically detecting a position of a designating device inserted into a flat or substantially flat two-dimensional coordinate inputting/detecting area of the apparatus includes a coordinates determining device to determine two-dimensional coordinates of the designating device in the coordinate inputting/detecting area at a predetermined time interval, and an insertion/non-insertion state detecting device to detect an insertion/non-insertion state of the designating device relative to the coordinate inputting/detecting area. A vetorization device converts information of a direction and a length of a change between two two-dimensional coordinates sequentially detected by the coordinates determining device at the predetermined time interval into a coordinates vector value. And, a trailing processing device processes, if a change of a first coordinates vector value, obtained by the vetorization device when the non-insertion state of the designating device is detected at a first two-dimensional coordinates by the insertion/non-insertion state detecting device, from a second coordinates vector value, obtained by the vetorization device immediately before the first two-dimensional coordinates, is greater than a predetermined value, a drawing line connecting between the first and second two-dimensional coordinates so as to be made null. Further, a trailing length calculating device calculates an average length value of the drawing lines made null by the trailing processing device. A sweeping up processing device processes, if the change of the first coordinates vector value, obtained by the vetorization device when the non-insertion state of the designating device is detected at the first two-dimensional coordinates by the insertion/non-insertion state detecting device, from the second coordinates vector value, obtained by the vetorization device at the second two-dimensional coordinates immediately before the first two-dimensional coordinates, is not greater than the predetermined value, a drawing line connecting between the second two-dimensional coordinates and a third two-dimensional coordinates immediately before the second two-dimensional coordinates so as to be reduced by a length of the average length value.
According to the present invention, in the above coordinate inputting/detecting apparatuses, the coordinates determining device may include a plurality of light emitting devices to emit optical beams two-dimensionally toward the coordinate inputting/detecting area, a light returning reflective device to reflect the optical beams emitted by the plurality of light emitting devices so as to return in substantially reverse directions in the coordinate inputting/detecting area, and a plurality of light receiving devices respectively disposed in positions to receive the optical beams reflected by the light returning reflective device so as to detect light intensity distribution of the optical beams. The designating device has a light interrupting property, and the two-dimensional coordinates of the designating device in the coordinate inputting/detecting area are recognized based upon the existence of the designating device in emitted/received light optical paths formed in the coordinate inputting/detecting area via the light returning reflective device, and the distance determining device determines the distance of the designating device from the surface of the coordinate inputting/detecting area based upon light intensity of the optical beams received by the plurality of light receiving devices.
Further, according to the present invention, in the above coordinate inputting/detecting apparatuses, the coordinates determining device may include an image inputting device to optically input image information of the coordinate inputting/detecting area, and a conversion device to convert a part of the image information input by the image inputting device to information of two-dimensional coordinates of the designating device. The distance determining device determines the distance of the designating device from the surface of the coordinate inputting/detecting area based upon image density information of the image information input by the image inputting device.
Furthermore, according to the present invention, in the above coordinate inputting/detecting apparatuses, the coordinates determining device may include a plurality of light emitting devices to emit optical beams toward the coordinate inputting/detecting area, a plurality of light receiving devices arranged in the vicinity of the plurality of light emitting devices so as to correspond to the plurality of light emitting devices, respectively, and a light returning reflective device to reflect the optical beams emitted by the plurality of light emitting devices so as to return to substantially the same positions as those of the plurality of light emitting devices to be guided to respective corresponding light receiving devices. The two-dimensional coordinates of the designating device in the coordinate inputting/detecting area are recognized based upon light intensity distribution corresponding to an inserted position of the designating device in the coordinate inputting/detecting area, and the distance determining device determines the distance of the designating device from the surface of the coordinate inputting/detecting area based upon light intensity of the optical beams received by the plurality of light receiving devices.
Still furthermore, according to the present invention, in the above coordinate inputting/detecting apparatus, the coordinates determining device may include a plurality of light emitting devices to emit optical beams two-dimensionally toward the coordinate inputting/detecting area, and a plurality of light receiving devices arranged in positions facing the plurality of light emitting devices via the coordinate inputting/detecting area, respectively. The designating device has a light interrupting property, and the two-dimensional coordinates of the designating device in the coordinate inputting/detecting area are recognized based upon the existence of the designating device in emitted/received light optical paths formed in the coordinate inputting/detecting area, and the distance determining device determines the distance of the designating device from the surface of the coordinate inputting/detecting area based upon light intensity of the optical beams received by the plurality of light receiving devices.